Initially all production acceptance testing for surface transportation vehicles was accomplished using conventional analog instrumentation. The instrumentation; consisting of signal conditioning, power supplies, calibration sources, and oscillographs, was contained in a two-bay equipment enclosure. The instrumentation's weight and physical size necessitated the use of forklift installation onto the test vehicle.
Operation of the instrumentation required a pre-test temperature stabilization and calibration of forty-five minutes, and the recording oscillograph data during testing. Post test oscillograph data reduction, necessary to satisfy all vehicle acceptance criteria, required approximately six hours to complete. Projecting these tasks and man hours over a production run of 550 vehicles emphatically showed that a more efficient method had to be developed for production acceptance testing.
A more effective method is described in a paper entitled "Application of the Microprocessor to Surface Transportation Vehicle Testing", published on May 2, 1978 by The Instrument Society of America. This paper contained a non-specific disclosure of the broad aspects of Applicants' invention.
The publication discloses components boards such as analog, speed, and control boards, and that some boards receive information from other boards. There is no specific description of what information is received or exchanged, nor is there an adequate disclosure of the electronic elements contained in the boards.
It is well known in the art to test vehicle parameters, but not in the manner of the present invention. The interrelation of the electronic circuit boards as specifically disclosed in the application yields a compact, precise and time-saving vehicle parameter testing device. Even though the board aspects of the invention have been published, the intermediate and specific aspects not disclosed are deemed patentable over the publication.